import { err, ok, type ReadonlyDB } from "@tailor-platform/erp-kit/core";
import type { DB } from "../generated/kysely-tailordb";
import { LeaveGrantNotFoundError } from "../lib/errors.generated";

export interface GetLeaveGrantInput {
  id: string;
}

/**
 * Function: getLeaveGrant
 * Retrieves a single LeaveGrant ledger record by id, regardless of whether
 * it is expired, partially consumed, or untouched. Returns the raw ledger
 * fields as stored; use getLeaveBalance for an aggregated balance.
 */
export async function run(db: ReadonlyDB<DB>, input: GetLeaveGrantInput) {
  const grant = await db
    .selectFrom("LeaveGrant")
    .selectAll()
    .where("id", "=", input.id)
    .executeTakeFirst();

  if (!grant) {
    return err(new LeaveGrantNotFoundError(input.id));
  }

  return ok({ grant });
}